6th FERO meeting

ASTRONOMICAL INSTITUTE
ACADEMY OF SCIENCES, PRAGUE
Boční II 1401, 141 00 Praha 4
Czech Republic

30th – 31st of August 2012



Euro in Czech Crowns: 1€ = Kč
Metro-Tram scheme
Map of centre (more detailed)
    Participants

August



Frédéric Marin

X-ray polarimetry as a new and independent tool to discriminate reflection from absorption scenarios – Investigating the case of MCG-6-30-15

[presentation]

On the FERO meeting occasion, I will review the latest submitted paper wrote by Marin, Goosmann, Dovciak, Muleri, Porquet, Grosso, Karas and Matt concerning the modelling of X-ray polarization spectra emerging from the two competitive scenarios that are proposed to explain the broad Fe Kα line in MCG-6-30-15. In the submitted letter, the polarization signature of complex absorption was studied for a partial covering scenario using a clumpy wind and compared to a reflection model based on the lamp-post geometry. The shape of the polarization percentage and angle as a function of photon energy were found to be distinctly different between the reflection and the absorption case. Indeed, the relativistic reflection produces significantly stronger polarization in the 1–10 keV energy band than absorption. The spectrum of the polarization angle adds additional constraints: in the absorption case it shows a constant shape, whereas the relativistic reflection scenario typically leads to a smooth rotation of the polarization angle with photon energy. Based on this work, we concluded that a soft X-ray polarimeter on-board a small X-ray satellite may already discriminate between the absorption and the reflection scenario. The small X-ray polarimetry mission XIPE, which has recently been proposed to the European Space Agency for a launch in 2017 and currently reviewed for a final decision in next September would be suitable in this respect.